Abstract

A method for precise measurement of absolute electron density in the plasma using plasma frequency is proposed. The phase difference between two antennas (radiating and detecting antennas) and its slow time modulation was used, instead of the transmittance used in previous cutoff probe, and a remarkable result is observed. This method can determine the absolute electron density precisely: It is not only in a good agreement with the previous method very closely but also is able to find the cutoff point clearly even in difficult conditions where there are ambiguities to determine the cutoff point with previous method.

Received 01 October 2009Accepted 25 January 2010Published online 25 February 2010

Acknowledgments:

This work is financially supported by the Ministry of Knowledge Economy (10031812-2008-11) and supported by KRISS. One of the authors would like to thank PLASMART. INC for its technical and financial support for this work.